CP and CPT measurements at DAFNE

Starting from the time evolution of the C-odd ${\bar{K}}^0{K}^0$ system, we analyze the asymmetries measurable at DAFNE and their implications on CP violation and on the possible tests of T and CPT symmetries. In particular the ratio ${ϵ}^{\mathrm{\prime }}\mathrm{/}ϵ$ can be measured with high precision (up to about ${10}^{-4}$ for the real part). The CP-, T- and CPT-violating parameters can be explored in $K_S$ semileptonic decays with an accuracy of the order of ${10}^{-3}$. The possibility to detect $K_S\to 3\pi$ and $K_L \to \pi \pi \gamma$ decays is also discussed.